Punching apparatus

ABSTRACT

The present punching apparatus is a so called clicking machine for producing shapes out of sheet material by means of punching tools. A punching table made of bendable material is pressed toward the punching tools by a presser cylinder as the cylinder is moved in contact with and along one surface of the bendable punching table while pressure is exerted against the opposite punching table surface by counter presser means through said tools and through said sheet material to be punched.

United States Patent Spengler 1 Nov. 21, 1972 [54] PUNCHING APPARATUS 2,237,449 4/1941 Ryan ..83/531 [72] Inventor: Ernst Maximilian p g Heusen Andoisek l0 X Stamm near Offenbach am Main 3,570,340 3/1971 Rohdm ..83/512 Germany 3,213,737 10/1965 Wright ..83/510 X 3,024,688 3/1962 Romm ..83/510 X [73] Assignee: Roeder & Spengler OHG, Bergen- Enkhelm, Germany Primary Examiner-James M. Meister [22] Filed; April 27, 1970 Attorney-Wolfgang G. Fasse [21] Appl. No.: 32,294 [57 ABSTRACT The present punching apparatus is a so called clicking [30] Forms Apphcatlon Pnomy Dam machine for producing shapes out of sheet material by May 7, 1969 Germany 9 1 4754 means of punching tools. A punching table made of April 4, 1970 Germany P 20 16 1824 bendable material is pressed toward the punching tools by a presser cylinder as the cylinder is moved in [52 US. Cl. ..83/542, 83/510, 83/564 Contact with and along one surface of the bendable [51] Int. Cl ..B26d 5/08, B26f 1/42 p g table while p e is e e ted g t the [58] Field of Search ..83/510-512, 531, pp site punching table surface by counter presser 83/542, 564 means through said tools and through said sheet t Y material to be punched. 56 R t 1 e erences cued 6 Claims, 3 Drawing Figures UNlTED STATES PATENTS '7 V l v 7 2,688,367 9/1954 Maeser ..83/512 6 L L m i 1 w 2 I3 1 I4 I5 PATENTEDNHVZI m2 SHEETIHFZ PUNCHING APPARATUS The present invention relates to a punching apparatus for stamping or punching workpieces from sheet material, for example, for cutting pieces of cloth of predetermined size and shape, so called patterns, from webs of cloth for the production of ready-made clothing.

Stamping or punching devices suitable for the above and other purposes are known in the art and different embodiments or constructions are available.

One construction which is known as a rotary punching apparatus employes a stationary punching table on which the material to be punched, out or stamped is located while the punching tools or dies are arranged on the circumference of a cylindrical roller. The workpieces are punched out by rolling the die carrying roller relative to and on the punching table. A drawback of this known construction is seen in that the sheet material or webbing to be punched out is subjected to distortion due to the substantial pressure which is supplied to the punching roller whereby such distortions result in warping and buckling. As a result the punched patterns frequently do not meet the size and shape requirements.

Another disadvantage of the punching apparatus employing a rotary punching cylinder or roller is seen in that the material to be punched, and especially soft material, forms a so called bow-wave which is pushed ahead of the punching roller whereby the material is also distorted due to such bow-wave. In this instance as well as in the first mentioned instance the punched out pattern will not have the desired size and shape.

The above considerations also apply to known constructions or punching devices which are referred to as roller punches in which the punching dies or tools are supported in a plane and the stamped out pattern is formed by two presser rollers. The stamping tools or dies as well as the material to be punched are moved through a gap between the two presser rollers as part of the punching operation.

A third group of known punching devices comprises so called bridge punches and swivel arm punches. These devices have the advantage that material distortions due to the formation of said bow-waves, is avoided. However, the drawback of this group is seen in that a very high punching pressure is required.

OBJECTS OF THE INVENTION In view of the foregoing it is an object of the invention to remove the outlined drawbacks.

More specifically, it is an object of the invention to avoid distortions of the material to be punched so that the material will neither be buckled nor warped and the punched out workpieces will retain their size and shape.

It is yet another object of the invention to avoid unusually high stamping or punching pressures.

Yet another important object of the invention is to completely depart from the prior art by avoiding a direct contact between either a tool carrying punching roller and the material to be punched or between a presser roller and the material to be punched.

A still further object of the invention is to provide a bendable or flexible punching table between the material to be punched and a presser cylinder whereby the pressure is supplied indirectly to the material.

Another object of the invention is to provide con-' veyor means which advance the material to be punched on to a bendable or flexible punching table, preferably in a direction which extends across the direction of movement of a presser cylinder.

SUMMARY OF THE INVENTION The above objects have been achieved according to the invention in that the punching table of the present punching apparatus is made of a flexible or bendable material which carries the material to be punched and preferably also the punching tools or dies which, in the simplest version, are placed on top of the material to be punched. In another version the punching tools are supported above the material by counter presser means arranged above the punching table. A presser cylinder is arranged underneath the punching table. The presser cylinder is movable perpendicularly to its longitudinal axis, for example, on guide means such as rails supported in a machine frame in such a manner that a presser roller can move along the entire extent of the punching table.

In order that the invention may be clearly understood it will now be described, by way of example, with reference to the accompanying drawings, wherein:

FIG. 1 is a diagrammatic side view, partially in section, of a punching apparatus according to the invention;

FIG. 2 illustrates on an enlarged scale means for resiliently supporting the punching table as shown on a smaller scale in FIG. 1; and

FIG. 3 shows in diagrammatic form the operation of the present punching apparatus whereby structural details which are not essential for the function of the apparatus have been omitted;

DESCRIPTION OF EXAMPLE EMBODIMENTS Referring to FIG. 1 there is shown a machine frame 1 of the punching apparatus. Guide means, for example, a pair of guide rails 2, are supported on the machine frame 1 in a fixed position. A presser cylinder 4 is movable back and forth along the guide rails 2 as indicated by the horizontal double arrow. Preferably the presser cylinder 4 is supported on the guide rails by means of a pair of rollers 3 which will be described in more detail with reference to FIG. 3. The presser cylinder 4 has a longitudinal axis or shaft which is supported by bearing means, for example by sleeve or ball bearing means, arranged at the end of a piston rod 5 which is moved back and forth by a piston cylinder arrangement 6 attached to the machine frame 1. The piston cylinder arrangement 6 may be driven by a hydraulic or a pneumatic power source not shown but will known.

The punching table 7 which, according to the invention, is made of a bendable or resilient material, is supported in the machine frame 1 above the guide rails 2 and above the presser cylinder 4 by means of adjustable and elastically yielding connecting means 8, 9, and 10 which will be described in more detail with reference to FIG. 2. The spacing between the punching table 7 and the guide rails 2 is selected so that the punching table 7 is in exact contact with the presser cylinder 4.

The punching table 7 is produced, for example, as a layered and/or coated metal webbing, or the punching table 7 is made of a sheet of hardened steel or of a relatively thin steel plate which is polished or ground to a fine surface finish, such metal webbing or sheet of steel providing the bendable material as taught by the invention.

The punching table 7 is supported by said connecting means comprising a table frame 8 which in turn is connected to the machine frame 1 by means of springs 9 as best seen in FIG. 2. The spring 9 is connected at one end to the table frame 8 and at the other end by means of a threaded bolt to the machine frame 1 whereby the tension of the spring 9 is adjustable by means of a wing nut 10.

A counter presser means, for example, in the form of a plate 11 is movably supported on the machine frame.

1, for example, by journal means whereby the counter presser plate 11 is tiltable up and down as indicated by the upper double arrow in FIG. I.

The counter presser plate 11 carries the punching dies 12, for example, in the form of strip steel knives supported by the counter presser plate in a so called floating manner, for example, by magnetic means forming part of the counter presser plate 11.

The counter presser means or plate 11 comprises a hinge axis 11a and a rear extension 13 connected to a piston rod 14 which is actuated by a piston cylinder arrangement 15 for moving the rear extension 13 from the full line position in which the counter presser plate 11 is in its open position, to a position indicated by a dash-dotted line in which the counter presser plate 11 is in its closed position also as indicated by a dashdotted line in FIG. 1. The piston cylinder arrangement 15 may be operated by the hydraulic or pneumatic power source which also operates the arrangement 6. When the counter presser plate 11 has reached its closed horizontal position above the punching table 7 it is automatically locked against an upwardtilting by means of a suitable locking device comprising, for example, a hook 16 attached to the front edge of the counter presser plate 1 1 and a catch 17 attached to the machine'frame 1. The locking device must be released prior to lifting or tilting the counter presser plate 11 in the upward direction.

The exact position of the counter presser plate 11 relative to the punching table 7 may be adjusted, for example, by shifting the axis on which the counter presser plate 11 is journaled in .an upward or downward direction. Modified means for adjusting the position of the counter presser means relative to the punching table 7 are described with reference to FIG. 7.

Control means 18 are supported on one side of the machine frame 1 for controlling the locking device 16, 17 and/or the operation of the piston cylinder arrangements 6 and 15. Such control means are well known in the art.

The operation of the present invention will now be described with reference to FIG. 3. The material 19 to be punched is placed on top of the bendable punching table 7. The punching tools in the form of strip steel knives 12 are placed on top of the material 19 and the counter presser plate 11 is forced against the knives by the punching force .P which may, for example, be exerted by the piston cylinder arrangement 15 shown in FIG. 1. As a result, the bendable punching table 7 yields slightly downwardly and the material 19 is compacted in the places where the edges or lines of the knives 12 contact the material 19.

In this connection it should be noted that the areas 20 of the material 19 which are not subjected to the action of the punching knives l2 retain their normal thickness or in any event a larger thickness than the areas in contactwith the cutting lines or edges of the punching knives 12 whereby a distortion of the material 19 is avoided.

While the punching force P is maintained as described above, the presser cylinder 4 is moved'along and in contact with the table 7 whereby the table is lifted in successive areas 21 which are in contact with the surface of the presser cylinder 4.

In order to compensate for the thickness and the yieldability or compactability of the material 19 it is desirable to adjust the spacing between the punching table '7 and the counter presser plate 11 as described above and to also adjust the tension of the punching table 7, for example, by tightening or loosening the wing nuts 10.

As the presser cylinder 4 moves from its extreme left hand position to its extreme right hand position driven by the piston cylinder arrangement 6 the pattern defined by the knife edges is punched out successively from left to right. It is a particular advantage of the present invention that the force needed for moving the presser cylinder 4 is smaller. than the dynamic-force needed for punching such patterns by means of known devices, for example a bridge punching device. Incidentally, the hydraulic or pneumatic piston cylinder arrangements 6 and 15 may be replaced by an electric motor which could drive the presser cylinder 4, for example, by means of a pinion and rack device.

Another important advantage of the invention is seen in that a complete set of patterned workpieces may be cut when the presser cylinder 4 moves in one direction while a further set of workpieces is out while 5 the presser cylinder 4 moves in the'opposite direction so that there is no idling movement.

Control devices for reversing the direction of move-. ment of the presser cylinder 4 are well known in the art. This applies also to mechanical and/or electrical switching means for actuating said control means.

Referring further to FIG. 3 it will be noted that the presser cylinder 4 is supported by rollers 3 for riding along the guide rails 2. The rollers 3 are in turn supported in pairs in a roller carriage 3a having a curved upper portion 3b with pointed end members 30 arranged in such a manner that the presser cylinder 4 rests against the rollers 3 but is prevented from rolling off the rollers 3 by the end members 3c which form with the curved portion 3b a cradle for the presser cylinder 4. The rollers 3 may be in the form of roller rods extending along the length of the presser cylinder 4 and rotatably supported in the roller carriage 3a.

I claim:

1. In a punching apparatus wherein the following elements cooperate for punching shapes out of flat material, a punching table having opposite ends, pressure roller means, and counter pressure means as well as punching tools between the punching table and the counter pressure means and drive means for said pressure roller means which are supported by a frame structure having an opening therein, the improvement comprising in combination:

a. a hinged cover member forming said counter pressure means;

b. a sheet of bendable material for forming said punching table;

c. resilient means secured to said sheet adjacent to opposite ends thereof and to said frame structure at opposite sides thereof for resiliently stretching said sheet substantially horizontally across said opening in said frame structure;

. a single pressure roller;

e. guide means supported in said frame structure below said opening and spaced therefrom for rotatably supporting said pressure roller in contact with said sheet of bendable material when the pressure roller is reciprocated by said drive means back and forth underneath said sheet;

f. hinge means for tiltably connecting the counter pressure cover member to said frame structure adjacent to one side thereof whereby the hinge means lock the cover member in its closed position to the frame structure at said one side thereof; and

g. latching means for positively locking said counter pressure means to the other side of the frame structure.

2. The punching apparatus according to claim 1, further comprising tilting means for said counter pressure cover member, said tilting means comprising a piston cylinder arrangement supported in the frame structure and a piston rod, said cover member including an extension connected to said piston rod for opening and closing the cover member by tilting it about said hinge means.

3. The punching apparatus according to claim 2, wherein said hinge means act as first means for positively locking the counter pressure plate to said frame structure adjacent to the opposite end of the punching table, and wherein said latching means act as second means for positively locking the counter pressure cover member to the frame structure adjacent to one end of the punching table.

4. The punching apparatus according to claim 1, wherein the guide means for the single pressure roller comprise guide rails supported in the frame structure and extending perpendicularly to a longitudinal axis of the pressure roller and guide roller means including a roller carriage arranged between the pressure roller and said guide rails whereby the guide roller means roll along said guide rails and simultaneously rotatably support the pressure roller in said roller carriage which forms a cradle with a curved upper portion and with pointed end members arranged so that the pressure roller rests in said cradle against said guide roller means whereby said pointed end members prevent the pressure roller from rolling off said guide rollers.

5. The punching apparatus according to claim 1, wherein said sheet of bendable material is made of steel.

6. The punching apparatus according to claim 1, wherein said sheet of bendable material is made of metal webbing. 

1. In a punching apparatus wherein the following elements cooperate for punching shapes out of flat material, a punching table having opposite ends, pressure roller means, and counter pressure means as well as punching tools between the punching table and the counter pressure means and drive means for said pressure roller means which are supported by a frame structure having an opening therein, the improvement comprising in combination: a. a hinged cover member forming said counter pressure means; b. a sheet of bendable material for forming said punching table; c. resilient means secured to said sheet adjacent to opposite ends thereof and to said frame structure at opposite sides thereof for resiliently stretching said sheet substantially horizontally across said opening in said frame structure; d. a single pressure roller; e. guide means supported in said frame structure below said opening and spaced therefrom for rotatably supporting said pressure roller in contact with said sheet of bendable material when the pressure roller is reciprocated by said drive means back and forth underneath said sheet; f. hinge means for tiltably connecting the counter pressure cover member to said frame structure adjacent to one side thereof whereby the hinge means lock the cover member in its closed position to the frame structure at said one side thereof; and g. latching means for positively locking said counter pressure means to the other side of the frame structure.
 1. In a punching apparatus wherein the following elements cooperate for punching shapes out of flat material, a punching table having opposite ends, pressure roller means, and counter pressure means as well as punching tools between the punching table and the counter pressure means and drive means for said pressure roller means which are supported by a frame structure having an opening therein, the improvement comprising in combination: a. a hinged cover member forming said counter pressure means; b. a sheet of bendable material for forming said punching table; c. resilient means secured to said sheet adjacent to opposite ends thereof and to said frame structure at opposite sides thereof for resiliently stretching said sheet substantially horizontally across said opening in said frame structure; d. a single pressure roller; e. guide means supported in said frame structure below said opening and spaced therefrom for rotatably supporting said pressure roller in contact with said sheet of bendable material when the pressure roller is reciprocated by said drive means back and forth underneath said sheet; f. hinge means for tiltably connecting the counter pressure cover member to said frame structure adjacent to one side thereof whereby the hinge means lock the cover member in its closed position to the frame structure at said one side thereof; and g. latching means for positively locking said counter pressure means to the other side of the frame structure.
 2. The punching apparatus according to claim 1, further comprising tilting means for said counter pressure cover member, said tilting means comprising a piston cylinder arrangement supported in the frame structure and a piston rod, said cover member including an extension connected to said piston rod for opening and closing the cover member by tilting it about said hinge means.
 3. The punching apparatus according to claim 2, wherein said hinge means act as first means for positively locking the counter pressure plate to said frame structure adjacent to the opposite end of the punching table, and wherein said latching means act as second means for positively locking the counter pressure cover member to the frame structure adjacent to one end of the punching table.
 4. The punching apparatus according to claim 1, wherein the guide means for the single pressure roller comprise guide rails supported in the frame structure and extending perpendicularly to a longitudinal axis of the pressure roller and guide roller means including a roller carriage arranged between the pressure roller and said guide rails whereby the guide roller means roll along said guide rails and simultaneously rotatably support the pressure roller in said roller carriage which forms a cradle with a curved upper portion and with pointed end members arranged so that the pressure roller rests in said cradle against said guide roller means whereby said pointed end members prevent the pressure roller from rolling off said guide rollers.
 5. The punching apparatus according to claim 1, wherein said sheet of bendable material is made of steel. 